USB: ohci-spear: Make of_device_id array const

Make of_device_id array const, because all OF functions handle
it as const.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/host/ohci-spear.c b/drivers/usb/host/ohci-spear.c
index 8b29a0c..8d58766 100644
--- a/drivers/usb/host/ohci-spear.c
+++ b/drivers/usb/host/ohci-spear.c
@@ -162,7 +162,7 @@
 }
 #endif
 
-static struct of_device_id spear_ohci_id_table[] = {
+static const struct of_device_id spear_ohci_id_table[] = {
 	{ .compatible = "st,spear600-ohci", },
 	{ },
 };